<div class="problemindexholder" problemindex="A">
 <div class="ttypography">
  <div class="problem-statement">
   <div class="header">
    <div class="title">
     A. Chess Tourney
    </div>
    <div class="time-limit">
     <div class="property-title">
      time limit per test
     </div>
     1 second
    </div>
    <div class="memory-limit">
     <div class="property-title">
      memory limit per test
     </div>
     256 megabytes
    </div>
    <div class="input-file">
     <div class="property-title">
      input
     </div>
     standard input
    </div>
    <div class="output-file">
     <div class="property-title">
      output
     </div>
     standard output
    </div>
   </div>
   <div>
    <p>
     Berland annual chess tournament is coming!
    </p>
    <p>
     Organizers have gathered
     <span class="tex-span">
      2·
      <i>
       n
      </i>
     </span>
     chess players who should be divided into two teams with
     <span class="tex-span">
      <i>
       n
      </i>
     </span>
     people each. The first team is sponsored by BerOil and the second team is sponsored by BerMobile. Obviously, organizers should guarantee the win for the team of BerOil.
    </p>
    <p>
     Thus, organizers should divide all
     <span class="tex-span">
      2·
      <i>
       n
      </i>
     </span>
     players into two teams with
     <span class="tex-span">
      <i>
       n
      </i>
     </span>
     people each in such a way that the first team always wins.
    </p>
    <p>
     Every chess player has its rating
     <span class="tex-span">
      <i>
       r
      </i>
      <sub class="lower-index">
       <i>
        i
       </i>
      </sub>
     </span>
     . It is known that chess player with the greater rating always wins the player with the lower rating. If their ratings are equal then any of the players can win.
    </p>
    <p>
     After teams assignment there will come a drawing to form
     <span class="tex-span">
      <i>
       n
      </i>
     </span>
     pairs of opponents: in each pair there is a player from the first team and a player from the second team. Every chess player should be in exactly one pair. Every pair plays once. The drawing is totally random.
    </p>
    <p>
     Is it possible to divide all
     <span class="tex-span">
      2·
      <i>
       n
      </i>
     </span>
     players into two teams with
     <span class="tex-span">
      <i>
       n
      </i>
     </span>
     people each so that the player from the first team in every pair wins
     <span class="tex-font-style-bf">
      regardless
     </span>
     of the results of the drawing?
    </p>
   </div>
   <div class="input-specification">
    <div class="section-title">
     Input
    </div>
    <p>
     The first line contains one integer
     <span class="tex-span">
      <i>
       n
      </i>
     </span>
     (
     <span class="tex-span">
      1 ≤
      <i>
       n
      </i>
      ≤ 100
     </span>
     ).
    </p>
    <p>
     The second line contains
     <span class="tex-span">
      2·
      <i>
       n
      </i>
     </span>
     integers
     <span class="tex-span">
      <i>
       a
      </i>
      <sub class="lower-index">
       1
      </sub>
      ,
      <i>
       a
      </i>
      <sub class="lower-index">
       2
      </sub>
      , ...
      <i>
       a
      </i>
      <sub class="lower-index">
       2
       <i>
        n
       </i>
      </sub>
     </span>
     (
     <span class="tex-span">
      1 ≤
      <i>
       a
      </i>
      <sub class="lower-index">
       <i>
        i
       </i>
      </sub>
      ≤ 1000
     </span>
     ).
    </p>
   </div>
   <div class="output-specification">
    <div class="section-title">
     Output
    </div>
    <p>
     If it's possible to divide all
     <span class="tex-span">
      2·
      <i>
       n
      </i>
     </span>
     players into two teams with
     <span class="tex-span">
      <i>
       n
      </i>
     </span>
     people each so that the player from the first team in every pair wins regardless of the results of the drawing, then print
     <span class="tex-font-style-tt">
      "YES"
     </span>
     . Otherwise print
     <span class="tex-font-style-tt">
      "NO"
     </span>
     .
    </p>
   </div>
   <div class="sample-tests">
    <div class="section-title">
     Examples
    </div>
    <div class="sample-test">
     <div class="input">
      <div class="title">
       Input
      </div>
      <pre>2<br/>1 3 2 4<br/></pre>
     </div>
     <div class="output">
      <div class="title">
       Output
      </div>
      <pre>YES<br/></pre>
     </div>
     <div class="input">
      <div class="title">
       Input
      </div>
      <pre>1<br/>3 3<br/></pre>
     </div>
     <div class="output">
      <div class="title">
       Output
      </div>
      <pre>NO<br/></pre>
     </div>
    </div>
   </div>
  </div>
  <p>
  </p>
 </div>
</div>
